Eating more protein is linked to a smaller waist and better cholesterol levels, a new study finds

Researchers at the US Army Research institute of Environmental Medicine found an association between habitually consuming protein in excess of the recommended dietary allowance (RDA) and lower body mass index, a smaller waist, and higher levels of the HDL “the good” cholesterol (1). The findings published in the Journal of Nutrition, are from protein intake and cardiovascular risk factors that were assessed in approximately 24,000 US adults over a nine-year period.

In regards to this study authors Stefan Pasiakos, Harris Lieberman and Victor Fulgoni noted, “These findings are consistent with previous studies and suggest that the cardiometabolic advantages of higher-protein diets are largely independent of energy, carbohydrate, and fat intake, but appear limited to HDL cholesterol, waist circumference, and BMI.”

The results contradict recommendations established by the Dietary Guidelines for Americans. For instance, the RDA is currently 0.8 grams per kilogram, so for a 150-pound woman this translates into roughly 55 grams of protein per day. A higher protein diet would be 1 to 1.5 grams per kilogram equating to 70 to 100 grams for the same 150-pound woman.

Historically, nutritionists have been skeptical over eating a high-protein diet usually because of potential long-term adverse health effects (2;3). Some studies have suggested that over-consuming protein like red meat may increase cardiovascular risk factors and all-cause mortality (4-6). However, the newer research has all but exonerated high-protein diets of these concerns.

Higher protein diets also remain popular and for good reason—people who consume more find they have an easier time managing weight and preserving muscle during weight loss (1). In a systematic review published in the Journal of The American College of Sports Nutrition, the authors concluded, “There is convincing evidence that a higher protein intake increases thermogenesis and satiety [fullness] compared to diets of lower protein content. The weight of evidence also suggests that high protein meals lead to a reduced subsequent energy intake (7).”

Health benefits from a higher protein diet are often greater than those observed when eating a lower-fat, higher-carbohydrate diet consistent with the 2010 Dietary Guidelines for Americans and recommendations of the American Heart Association (8).

Researchers from this study found the health effects of higher-protein diets were greater in overweight individuals with positive effects on HDL cholesterol, waist circumference, and BMI. In fact, the good cholesterol HDL was 15 percent higher in those who ate more protein. Moreover, no negative association was found between higher protein intake and cardiovascular disease risk (1).

Nutrition researchers stress that the RDA of 0.8 grams per kilogram for protein represents the minimum amount of protein required to avoid deficiency (9). Numerous previous studies also show advantages of consuming protein in excess of the RDA (10-13).

Ideally, high-quality protein like whey should be consumed because of its advantages of helping maintain muscle during weight reduction. Whey is also relatively low in calories making supplementation convenient for promoting muscle building while promoting breakdown of fat. Researchers confirmed whey’s benefits in a 12-week trial that involved overweight subjects consuming whey protein at breakfast and dinner (14).

What the new study confirms is that higher protein intake is associated with reduced obesity. More specifically, decreased waist circumference and body mass index suggesting that visceral fat was lower for Americans consuming higher-protein diets.

For consumers wanting to lose weight, the new study adds more evidence that eating more protein than the RDA is not only safe, but is also a valid nutritional tool to improve cardiovascular health and bodyweight.